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The Cost of Distributed Client Computing?
ialbert asks: "I only recently decided to install SETI@home on my mostly idle home computer. It got me thinking though, are those free processor cycles truly free? Has anyone had experience with processors dying prematurely due to a constant, heavy load, or is usage pretty inconsequential? What about other components, like harddrives? And how much does a 100% processor load increase your power bill versus a 1-2% idle load over the course of a year? It's easy to think of idle computers as an untapped computational resource, but what are the costs to the computer owners?"
what are the costs to the computer owners?
$4.23
Next question?
While it is an interesting question, the reason you donate cycles to seti/columb rulers/cancer research/whatever is you love science and the progress of humanity.
:)
Its not about money.
Or to put it another way. How much CPU cycles are wasted on Pr0n, and how does this help society?
Excuse the Unicode crap in my posts. That's an apostrophe, and slashdot is busted.
I used to run a protien folding application on a spare Athlon I had. I thought it would help advance humanity. Then I discovered that the deamon I was running was spining my hard drive up and down all the time. Eventually the bearing gave out, and the disk platter came flying out of the case at high speed. It sliced through my cat and embedded itself in the oposite wall. The computer itself then caught fire when the drive motor over heated. It burnt my entire house and all of the contents, including a twelve thousand page thesis I had been working on (That work is classified, so I can't tell you what it was about). I stubbed my toe escaping, and a fire fighter died trying to put the fire out.
Just don't bother is my advice.
People don't buy a Cray or Origin cluster to have the CPUs sitting at 1% load, they're made to work. If a home PC was properly cooled I'd hope that it should last to whatever the lifetime is spec'd at by the manufacturer.
Trolling is a art,
Since there aren't any moving parts inside the processor, processor load is unlikely to wear it out. It is more likely that a processor will fail due to issues with cooling and from being turned on and off frequently. So keep that Seti@Home going!
I've noticed a significant difference in my electric bill if I don't use the suspend function in my computer. I don't have the bills in front of me but maybe $10 a month. I'm using one of the early, high-power consuming P-IIs though.
somebody worked this out when i started the e2 distributed.net team.
the figures
I've found that on my laptop, the cost of running seti@home cuts my battery life in half, so when I care about power I am sure to leave it off, however, when ever it's plugged in, it like the rest of my boxes are chugging away. When it comes to power costs I don't really care currently as I don't pay my electricity, it's included with my rent and believe you me I make good use of that.
As for premature death of CPU, being under heavy load should not hurt it, powering on and off often does far more 'wear and tear'.
Help Brendan pay off his student loans
Since I figured the cost of the processor running at 100% was insignificant compared to the cost of the hard drive constantly spinning instead of spinning down during downtime, I created a small RAM drive on my various computers where I ran seti@home so that the file access wouldn't affect hard drive usage. This worked equally well on linux and windoze. The only other thing to do was to create startup and shutdown scripts to create the ram drive, copy the files over, and start the process and then to copy off the files before shutdown.
Why do I h8 apple?
When Folding@Home is turned off, my power consumption for the entire system is 140W. When I activate Folding@Home, the Wattmeter reading jumps to about 190-195W.
So if you're concerned about electricity usage in your house, then yes, distributed computing sucks more power.
Homestarrunner.net -- It's Dot Com!
Most processors actively turn the clock off to parts of the chip that are not being used. So when you are doing nothing the processor is doing much less than when you have the computer do something.
The costs will be a lot higher if we don't detect and defeat the alien hordes through SETI.
I hate penny-pinching accountant types.
I've been using http://www.distributed.net/ on and off for a few years now and i've never had a problem with any of my processors. However I usually upgrade my cpu/mb every 3-4 years, so if you have or keep your systems longer i'd imagine any burnouts would be due to "just an old cpu" and not from the constant use. Then again I don't plan or expect my hardware to last forever.
As far as the power bill goes. I currently have a desktop, laptop, wireless router/hub and zaurus going the majority of the day - at least the systems are always on since I am too lazy to turn them off and have no need too. I also live with my girlfriend who runs the haridryer every morning and must have every light on in the house to check her makeup with. At the end of the month we get our power bill of $45-50 - which in my opinion is not a lot. We're also in California for the record.
Ave Molech Setting
I'm kinda in a position to answer at least one part of this question.
CPu's, when idle, can use as little as 2-5W. When fully utilized, up to 40-50W (depending on the make/model/etc). So let's assume you have a middle of the road processor that has a difference of 25W between active and idle. (This is consistant with measurements on a PIII 800MHz, a little lower than middle of the road.)
Now, 25W * 24Hrs * 365 days * 1kw/1000W * $0.10/kWhr = $21/year. Roughly $1/year per Watt of additional power.
As far as breaking of components, as well as the system is cooled properly, I wouldn't think it would be a problem.
I demand a million helicopters and a DOLLAR!
From what i understand,
if you are useing an overclocked Intel chip,
then yes, as they change the cycles to suite
the load and heat, you may age the chip,
but the ageing is only slight.
On AMD chips, they run the same weather under
load or not, so theres no ageing there.
Most of the damage to chips happens durning
booting up, powering down and spikes and surges.
Overclocking's Impact on CPU Life
You have 5 Moderator Points!
Which Helpless Linux zealot/MS basher do you want to mod down today?
Check this website for a breakdown of the energy costs.
http://www.dslreports.com/faq/2404
running a NOP draws less power than running a calc. CPU's get warmer (and are happier -- being all warm and fuzzy) when they're doing intense calculation work because they're exercising more transistors (got to keep in shape, you know).
My apc backups rs reports how much power is being used. When im at 100% cpu vs ~0% its an extra 17 watts.
For a 19" monitor + p3 + hard drives etc, its only about 220W total from the ups. (im sure much more peak from a cold start).
It's about 50-70 watts on the latest 3GHz PCs. An idling 3GHz Pentium 4 takes about 20 watts and a fully loaded one about 70-90 watts. At 15 cents the kilowatt-hour (that's what NYC pays), that comes out to an extra 21.6 cents/day or $79 per year compared to leaving the computer idle all year long.
So, yes, power is a substantial cost consideration. NYC power is also primarily gernerated with coal, so every joule of electricity used is that much more CO2 in the atmosphere. On the other hand, if the CPU cycles are going to a good cause, $79 is a quite affordable donation.
Right, and the standard in the ASIC industry is a 40 year lifetime minimum before electromigration will lead to failure in normal use (which means yo keep the chip in the allowed operating temperature range, regardless of if it's overclocked or not). That's 40 years. What hardware were you using 40 years ago?
Point is, even running chips hot, to a degree, (pun not intended) doesn't reduce their lifetime enough to worry.
Some of the other points, such as increased power use, and accelerated failure of mechanical components such as hard drives, are valid. But chip wear-out is a non issue -- you'd have to heat your chip past the point of system stability to get the em lifetime down low enough to care about it.
everything in moderation
The power costs are negligible on a single machine. Run a farm and it can get expensive when you factor in cooling, which is the primary expense. Air conditioning running 24/7 or close to it in a house is far more costly than the consumption of a typical PC.
The advantage of the heavy CPU usage clients like GIMPs is the fact they are often the first things to detect an impending CPU failure. My GIMPs client running on an Athlon wound up saving the machine. I brought it up to see its progress and it was reporting hardware register mismatches. Turns out the heat sink fan had failed and the CPU was overheating. Fortunately, there was enough supplemental cooling in the case to keep the chip from frying outright but Windows was chugging along fine without any indication of a problem while GIMPs was saying "turn me off or die".
These programs exercise the CPUs to limits that few programs ever use. They make wonderful test and benchmark applications. When Cray tested their supercomputer CPUs, they used to do prime number calculations since any error in the floating point hardware would come out instantly.
Uh .... NO.
That may have been true back in the bad old days of DOS, but today we have real operating systems. When there is nothing to due the OS exectues a HLT instruction which puts the CPU in a lower power state. There are numerous other ways to get to even lower power states that are required by ACPI which M$ has more or less REQUIRED all new computers to have in the past several years.
Also even when the CPU is going different codes will heat it up by different amounts. The P4 has a rather large differential b/w its maximum heat disipation and its 'typical' disipation, whereas the AMD Athlons are more consistent about their disipation.
<speculation>
I would assume what is happening is that the CPU 'powers down' parts of the core that are not being used ie an integer only code does not need the FPU/MMX/SSE etc units running so theoretically the CPU could block the clock from entering these units (since transistors more or less only generate heat when changing state ).
ps I am a 'software guy' not an EE
</speculation>
Thoughts on tech, Software Engineering, and stuff
Most modern processors, 68000 era and later, have a 'HALT' instruction which stops most of the internal 'ticking' of the CPU until an interrupt is received. On a CMOS CPU, your power use can go to approximately zero.
Check the boot messages on Linux; see the one where it says "Checking 'hlt' instruction"? That's what that is. Without hlt, the kernel has to do a no-op loop when there's nothing to run.
I believe all Windows NT versions (3.0 through 5.1 oops I mean XP) use hlt; there was some fuss about the DOS-based Windows not using it, but I don't care enough to look it up.
Yes, the grandparent post is incorrect.
Pentium IV CPUs have an internal temperture diode, just like every Intel chip since the Pentium II Deschutes core ( excluding early Celerons ).
As opposed to all chips before it, the Pentium IV will do more than just crash when overheating. It will dynamically reduce it's own clock speed to reduce power consumption. But this feature will only come into play when the cooling solution is unable to keep up with the processor ( IE: dead fan, extremely hot room ), and will not affect performance under normal conditions.
What the parent was referring to is the HLT instruction, which will cause the processor to do nothing and reduce power use. Most modern processors support it, and most modern operating systems ( including NT and Linux ) execute these instructions in an idle thread.
This is basically the concept of this discussion: will your computer run hotter under load rather than running idle HLT commands?
The answer is yes. What this means to you in terms of silicon lifetime is probably beyond the expertise of anyone here on Slashdot, so take every "insight" with a bag of salt.
Man is the animal that laughs.
And occasionally whores for Karma.
Has anyone had experience with processors dying prematurely due to a constant, heavy load, or is usage pretty inconsequential? What about other components, like harddrives? And how much does a 100% processor load increase your power bill versus a 1-2% idle load over the course of a year?
Those are all surprisingly complex and computationally intensive questions. In order to find the answer, I'll soon be releasing "@home@home", a distributed application designed to calculate the true cost of itself.
Please donate your spare CPU cycles to help fight cancer and other diseases
As a hardware design engineer, some facts are: The lifetime of a uP is based on the temperature of the silicon chip and hot spots on the chip. ---- Keeping the package cool with a good fan/heatsink so the temperature rise of the chip is only a few degrees will keep the chip alive for longer than you want to count. ----Power Cycling and its thermal cycling effect also reduces life, but you can expect the power switch to wear out long before the processor has a failure. You can also expect the power supply itself to have thermal shock failures long before the processor or other ICs. Remember, the low-voltage-reset (an internal circuit) keeps the processor from running during power up or down cycles so the effect is almost purely due to sudden heating and cooling as mentioned in the previous post.
Lol. At first I hated this guy because he was such a troll. But now when I read his posts I laugh. This guy posts the *exact* same text to zdnet talkback too. It's quite creative and would fool many normal users into thinking that it had a shred of credibility. Oh yea, if I remember correctly, this guy is regestered as Marvin Marvinski on zdnet. He claims to have a consulting company under the same name.
While I won't bore everyone with the differences between MTBF, FIT rate and what those numbers actually mean in an integrated circuit, let me assure you that 40 years is NOT the lifetime of a CPU. A CPU is NOT an ASIC and it never will be treated like one.
Design rules and electrical checks are supposed to give a level of assurance that there won't be reliability problems down the road but they are not perfect. Every chip has a flaw that will render it inoperable at some point; worst-case, a PN junction will start looking like a resistor and that will be it for that chip. That is WAY down the road though, so likely another flaw will be a chip's downfall.
Random flaws are the most common. Some of these cause very early failure (known as "infant mortality" failures, unfortunately) but some take much longer to cause devices to fail. Not just he metal lines, although that is one mechanism; void migration, defects in the thin oxide of the transistors, contamination... the list is long. And each wafer lot coming out of the fab may have a different set of defects; newer technologies like 0.13u and 0.09u (aka 90nm) are not yielding well due to the process not being fully worked out. The chips that do make it out are likely not as good as the ones that will come later as a result.
Now I'm not saying that current CPUs are going to start popping like popcorn due to heavy usage; just that there is going to be a wide distribution of the time that they fail. A 30+ watt CPU running full-tilt on a setiathome application is just not going to last 40 years (ignoring the usual issues of other components of the system dying before then). High junction temperatures have just a huge impace upon chip lifetimes and CPUs have the highest junction temps. They are not rated for 40 years at 100% activity -- don't you think there's a reason for a one to three year warranty?
- Leo
You don't use science to show that you're right, you use science to become right.
Many have pointed out that chips essentially don't wear out, but that's only in a world where every motherboard has a perfect design. In reality, given any motherboard, there will be some bad parts of the design and the lifetime may indeed be effected by how much it is stressed, especially those with an error in the design as regards to heat dissapation though underspeced drivers can be a big issue to. Also, many use capacitors whose values change after a few years due to chemicals cooking out of them. This is why many of the cheaper motherboards on the market will just stop working or become unreliable after about 3 years. If those motherboards are run hotter for a larger percentage of time, certainly there will be a reduction in life.
Even so, the cost amortized over time is still minor. If a motherboard goes bad after 2 years instead of 3, then you've "spent" 1/3 of the lifetime of a $100 or so component on the task. So, maybe about 34ish bucks split over 2 years or 17ish bucks a year. Not free, but not much money either.